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Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Bulking up CpBIG: A Penta-Terphenyl Cyclopentadienyl Ligand
Gabriele Hierlmeier1, Robert Wolf1
1Institute of Inorganic Chemistry, University of Regensburg, 93040 Regensburg, Germany.
Abstract:
The modification of cyclopentadienyl ligands with carefully selected substituents is a widely used strategy for tuning their steric and electronic properties. We describe the synthesis of an extremely bulky penta-terphenyl cyclopentadienyl ligand (CpT5) by arylation of cyclopentadiene. Deprotonation reactions with various group 1 metals and bases afforded a complete series of alkali metal salts MCpT5 (M = Li-Cs). The compounds were isolated as solvate-free salts, which were characterized by multinuclear nuclear magnetic resonance spectroscopy, ultraviolet-visible spectroscopy, and elemental analysis. Single-crystal X-ray diffraction studies of LiCpT5, NaCpT5 (crystallized as a solvate with one tetrahydrofuran molecule per formula unit), and KCpT5 revealed the formation of metallocene-like sandwich structures in the solid state.
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